MAGNETIC-FIELD ENHANCEMENT OF THE C-AXIS RESISTIVITY PEAK NEAR T(C) IN LAYERED SUPERCONDUCTORS

The contributions to the c-axis conductivity from fluctuations of the normal quasiparticle density of states are opposite in sign to the Asl amazov-Larkin and Maki-Thompson contributions, which lead to a peak in the overall c-axis resistivity rho(c)(T) above T(c). In a magnetic fi eld H parallel-to c, this peak increases in magnitude and is shifted t o lower T by an amount proportional to H-2 for weak fields and to H fo r strong fields. Our results are discussed in regard to recent experim ents with YBa2Cu3O7-delta and Bi2Sr2CaCu2O8+delta.